Ever since the 2015 World Cup defeat to Argentina in Cardiff, a large part of Joe Schmidt's modus operandi as Ireland's head coach has been to develop depth in his panel.

With a third of his starting team struck down one way or another before that last eight tie, the need for a wider pool was clear and the Kiwi has been true to his word. Thirty-two different players have been handed their debuts since that fateful afternoon in the Millennium Stadium and Ireland have even shown they can win big games without the likes of Conor Murray, Sean O'Brien, Jamie Heaslip and Peter O'Mahony.

There remains one exception to the rule though - Johnny Sexton sits in a class of his own. For years considered the side's most important player, he showed just why once again in Paris.

On a ground where he left the pitch battered and bruised on his past two visits, this time he was there to the bitter end, for all 83 minutes to be precise, and naturally it was he who had the final say.

With the most nerveless of last-gasp drop-goals, the two-tour Lion was pushed to the very edge of his limit to steal the 15-13 win for Ireland.

Lots had to go right for the visitors to be where they found themselves at the end of a mammoth 41-phase stretch - Iain Henderson's claim of the drop-out, Keith Earls soaring above Virimi Vakatawa, and carry upon carry from an exhausted set of forwards - but it was still fanciful to think they were in a position to win the game.

More than 40 metres from the posts, the fly-half was seemingly on the retreat as he took Murray's pass, but appeared to be the first man in Paris to know that his kick was good.

Often seen as a serious talent but equally serious man, there was a childlike glee on the former Racing 92 man's face as he broke French hearts in the city he briefly called home.

Wheeling away in celebration, he was back into his own '22' before he was finally caught, the first man jumping into his arms Bundee Aki.

"It just shows the heart that he has, how much courage he has and how much confidence he has in himself," said the Connacht man. "He obviously stood up there, put his hand up and nailed the kick.

"I think my first glance at it I just saw it go straight and it looked really good.

"We just turned around and just followed him.

'I don't think there was any doubt at all. There was a lot of belief from the boys.

"They trusted each other and trusted the process. The boys came in together in a huddle after that try was scored and they just said 'here, look we've got five minutes to do it and you want to do it, keep your hand up and keep going.'

"I think that's what the boys did. Leaders just led and the young fellas just followed on," Aki added.

While Sexton saved their bacon, it was a game Ireland should never have lost.

Two years ago in this fixture, Ireland dominated proceedings and were in a winning position, although not to the same degree as witnessed on Saturday, but found themselves missing out by a point thanks to a back-pedalling scrum and a moment of magic Maxime Medard.

This time it was Teddy Thomas with the inspiration, his 73rd minute try, and Anthony Belleau's conversion, nudging his side into a 13-12 lead.

Had that scoreline held up, it would have been a game filed firmly in drawer marked "ones that got away"

Speaking in the bowels of the Stade de France, Aki confirmed that Ireland's gameplan was to "just make sure we get over the advantage line, be direct, and then work from there."

While it made for a physically draining contest, and France were forced into a mammoth 238 tackles, Ireland's approach yielded not a single linebreak according to the official stat sheet, and there was precious little space when the ball was worked wide for the likes of Earls or Jacob Stockdale.

With Les Bleus working hard and showing a hitherto absent resolute streak in their first game under Jacques Brunel, four penalties, with one further miss from the tee, was all Ireland had to show for their efforts in regulation time, despite enjoying 68% of both possession and territory. For all the talk of how the visitors came to Paris deserving their position as 6-point favourites, the criticism would have been fierce if they had failed to win their opener for a third time in succession.

But just as if Sexton's kick falling short would have let the air out of the Irish balloon, the dramatic nature of the win, and three straight home games to come before the concluding fixture away to England on St. Patrick's Day, will have people already wondering if the late drama will go down in lore as a key moment of a championship campaign.

As soon as they recover from this most bruising of encounters, Aki predictably says the side will entertain no such thoughts and instead have only one thing on their mind - this week's visit from Italy.

"Whenever you play a physical side you're always going to be beaten up," he said.

"There are a whole lot of big boys in that team, and you certainly felt that out on the field. We've got to rest the bodies and make sure we're 100% again.

"We just said, we've got to work week on week. Focus on the first week, that was France and that was exactly what we needed to do.

"You can't look ahead, just focus on the week. This week we've just got to focus on getting the bodies right, getting back into Italy."